The speed of an electromagnetic wave is a constant, 3.0 × 108 m/s. the wavelength of a wave is 0.3 meters. what is the frequency? a. 9.0 × 108 hz b. 1.0 × 109 hz c. 1.0 × 108 hz d. 9.0 × 107 hz

option B. 1.0 × 10⁹ Hz

Explanation:

The speed, s, of a wave, equals the product of its frequency, ν, times its wavelength, λ:

As the question states, the speed of an electromagnetic wave is a constant, c, equal to 3.0 × 10⁸ m/s.

Substituting this constant in the equation for the speed of the wave, you get:

From that equation, you can solve for the frequency to show the inverse realation of frequency and wavelength:

Now, you just have to substitute values and compute:

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

i think it's 35 meters